Apparatus for rapid processing of film



Jan. 8, 1952 3, Mi T T r 2,582,182

APPARATUS FOR RAPID PROCESSING, OF FILM Filed June 26, 1948 INVENTORS T1.1 CLIFTON M. TUTTLE 1 PARIS H. STAFFORD BY v W q,

ATTORNE S Patented Jan. 8, 1952 APPARATUS FOR RAPID PROCESSING OF FILMClifton M. Tuttle, Halesite, and Paris H. Stafford,

Huntington, N. Y., assignors to Kenyon Instrument Company, Inc.,Huntington, N. Y.

Application June 26, 1948, Serial No. 35,494

6 Claims. 1

This invention has to do with apparatus for processing photographic filmwhich has been exposed. It is an improvement upon apparatus which wasdeveloped for rapid processing of photographs of the cathode-ray tubeface of a radar system. This apparatus for radar use, including acamera, a processing unit and a projector, came to be known as P 1 andis described in the Journal of the Franklin Institute, vol. 242, No. 3,September 1946, at pages 203 et seq.

In P 1, a strip of film is pulled intermittently along a track within alight-tight housing past a station where the image is produced and wherethe exposed film is processed, and thence past a station outside thehousing where the image is projected, one image being formed andprocessed while the one previously formed and processed is beingprojected. The film has its emulsion side uppermost and the exposure ismade through the film base by focusing the tube face, located below,through an aperture in the track. The processing cycle may be as shortas five seconds.

This rapid action is accomplished by delivering hot chemicals insequence to the unit which holds them at the film face. In P I this unitis an open plastic cup in the form of two concentric cylinders arrangedto drop onto the film from above at the processing station so thatthefilm forms the bottom of the cup and a seal is effected-by the lip orrim of the outer cylinder. After each of the hot chemicals (e. g., thedevelopenfixer and wash) has been delivered to the space within theinner cylinder and has had its effect on the emulsion, suction isapplied at the space between the cylinders to remove the chemical and todraw air rapidly over the film surface to dry it; whereupon throughaction of the controlling earns the delivery of the next chemical to thecup is initiated. The whole operation, including film movement anddelivery and exhaust of the chemicals and drying air, is controlled by abank of switches operated by a bank of cams on a single shaft whichmakes one full turn in the total cycle of about seconds.

The present improvement resides in the film processing unit. It is notlimited to use in the P 1 system, or to use for the purposes of thatsystem, but may be used in various systems for various purposes, andespecially where it is desired to obtain a photographic image of anobject which is in a transient condition (e. g., an oscillograph) orwhich is better observed in a. photographic image than in its reality(e. g., in photography by infra-red or ultra-violet wave lengths) andwhere it is desired to process the film with minimum delay in order thatthe information obtainable from the photograph may be available promptlyas a basis for taking a next step. There are also situations where it isdesirable to process the film immediately in order to preserve the imageagainst the effects of ambient radiation which would harm theundeveloped image, and the invention is useful in such situations asthose, as well as others.

A preferred form of the invention is described below with reference tothe annexed drawings, in which:

I Fig. 1 is a view in vertical section through the processing unitproper, with a diagrammatic showing of supply connections for theprocessing fluids.

Figs. 2 and 3 are, respectively, a plan and an elevation of one of thecomponents of the processing unit.

The film I0 is preferably, but not necessarily,

- in a horizontal plane at the processing station.

In the example shown, the film is at rest at the station; but the onlyessential is that it be at rest relative to the processin unit. Here thefilm is shown with the emulsion face at the lower side. The film ismoved intermittently by any suitable means to bring successive frames tothe processing station.

At this station is a fixed backing support for the film in the form of adisc ll of transparent plastic mounted in a fixed metal ring I! locatedabove the film track and close to the film. This backer presents a fiatsurface to the film at one side so that the film can be held fiatagainst it during the processing.

Below the film is the unit which during the processing forms a chamberthat is closed except for the inlet and outlet through which theprocessing 'fiuids pass under pressure. This unit provides for acontinuous fiow of each processing fluid ina confined thin stream acrossthe emulsion face of the film. It also includes means for bringing theparts which form this confined flow passage into working relation withthe film, involving a peripheral sealing engagement between the film andthe movable member which in conjunction with the film defines the fiowspace.

This lower unit consists of two main structural parts, an outer fixedelement [5 and an inner movable element l6 sliding in the fixed part sothat it can be brought into and out of engagement with the film. Themovable element It comprises the parts which define the fiow passage forthe processing fiuids. The processing unit shown here also includespneumatic means for moving the element It into and out of its engagementwith the film, certain parts of the fixed and movable elements being soshaped and related that they form two separate piston and cylinderunits. one for advancing the inner element |6 under air pressure and theother for retracting it by a suction action. Because of these piston andcylinder features, which preferably are cylindrical, both parts of theprocessing unit are of cylindrical shape generally; but it will beevident that this shape is not necessary.

Considering the fixed element 1 specifically, it has a main body part Iof hollow cylindrical shape with an inwardly projecting integral ring I!giving a smaller internal diameter at the lower part. It has a bottomclosure IS in the form of a transparent disc of plastic material whichfits within the central bore !9 and has a flange held in a recess 2| bya threaded retaining ring The upper and wider part of the central boreof this fixed element l5 receives the main cylindrical part of themovable element, while the smaller bore afforded by the rin I! receivesthe depending skirt part 25 of the movable element. Packing rings 21 and'28 seal the joints between the interfitting parts which provide the twopiston and cylinder units for actuating the movable element |5.

At one side of the fixed element l5, near its to the central bore is ata point just above the 9 bottom closure l8, thereby admitting air to thespace 33 within the depending skirt 26 of the movable element. Becausethere is a partition (described below) across the interior of themovable member, forming with the skirt 2 6 a piston sliding in thecylinder formed by the inward ring H, the compressed air admittedthrough passage 32 to the interior space 33 acts on this piston to causethe movable element to move upward toward the film.

At the other side of the fixed element 5 is another nipple 36 similarlythreaded into a tap in the wall and giving connection to a vacuum line31. A passage 38 in the wall of the fixed element leads upward from thistap through the ring I! to the annular space 39 beneath the main body 25of the movable element and between the outer wall of the skirt 26 andthe inner Wall of the fixed element 5. Thus the suction action serves toretract the movable element l6 by its action in this annular piston andcylinder unit formed by these coacting parts.

Near its upper end the movable element I6 has two nipples 4'3, 4|threaded into taps extending through the wall of the main body part '25at opposite sides. These furnish respectively the connections to thesupply line 42 and the exhaust line 43 for the processing fluids, sothat flow can be established through the interior chamber 44 in themovable element. This chamber 44 has a bottom closure formed by thetransverse partition 45 which is a disc of transparent plastic held in arecess 46 at the lower part of the main body of the movable element bythe threaded skirt 25 already mentioned. This bottom closure 45,together with the cylindrical main body part 25, form a cup shaped partthe peripheral rim of which engages the film around the area. to beprocessed to form a fluid tight joint, thereby P 4 forming the mainclosure for the processing chamber.

Integral with this partition 45 is a block 5|] of transparent plasticwhich is of smaller lateral size than the interior chamber 44. Thisblock 50 serves as a filler to reduce the free space within the cupshaped part of the movable element, and also serves to further definethe flow path for fluids passing from the inlet to the outlet. Itextends upward to a plane just short of the plane of the upper rim ofthe movable element Hi. When the movable element is brought into sealingengagement with the film at the peripheral rim 55, the top face 56 ofthe filler block 50 is slightly spaced below the emulsion face of thefilm, and so defines with it a shallow-flow passage across the filmface.

The upper rim 55 of the outer cylindrical part 25 of the movable element|5 is tapered to give a narrow surface engaging the film. This gives aneffective seal.

To confine the flow of processing fluids to the shallow passage at thefilm face, between the film and the top surface of the filler block 50,there are vertical fins 57 and 58 at the sides of the filler block 50midway between the inlet and outlet. These extend into contact with theinner wall of the bore in the movable element and pre vent flow aroundthe side of the filler block while providing some free space in theregions of the inlet and outlet connections to give easy flow to theshallow flow passage across the processing area.

It will be understood that the thin stream flow passage across the filmface may be obtained by other forms of construction. This use of anotherwise large chamber with a filler block is, however, a good way ofproviding wall area suflicient for good inlet and outlet fittings whilestill obtaining the thin stream flow across the film face which is animportant feature of this invention.

It will be noted from the above that all of the transverse parts aboveand below the film are din transparent, that is, the backer disc itabove the film, the filler member 59 and central partition 45 of themovable element It, and the end closure l8 of the stationary element l5.This permits light from a source 59 below the unit to pass through theentire unit, including the thin stream of processing fluid directlyunder the film, and the film itself to the extent permitted by the film.An optically selective filter 63 may be interposed between the lightsource and the processing unit to transmit only the desired visible butphotographically non-actinic light. If the light source is incorporatedin the processing unit above its bottom closure, the latter of coursemay be opaque.

This provision of a path for light has several purposes which will bebetter understood from what follows, although it will be evident withoutmore that one result is to make it possible to observe the film duringprocessing.

The chief features of this processing unit are that it provides a hollowmember open at one end which intermittently engages the film to form aclosed unit, completely sealed, through which the processing fluids maypass, and that at the zone of contact with the film it provides passagefor a thin stream of processing fluid passing under pressure in aconfined space across the surface of the film. This is the basic idea ofmeans with respect to the processing unit. This is in contrast to theknown system mentioned above in which each processing liquid stands in apool on the film and is withdrawn at the'endofits step-of processing.Within the limit of the requirements of this new idea, the constructionmay differ from that shown here.

The'further basic feature is the provision of a light path through theunit and across the film station. When used, this requires the use oftransparent material for all transverse members between the light sourceand the outer side of the backing member III, the transparent partsbeing in register with the film area to be processed and exposing asubstantial part or all of that area to the transmitted light.

A processing unit embodying either of these basic improvement features,or the other more specific features here illustrated, may be used withsystems of various sorts, manual or automatic, for effecting thedelivery and removal of the processing fluids. It may be used for avariety of types of processing; and with the transparent membersaffording a light path, it may be used for processing color film where asecond exposure is made during the processing. I illustrate its use hereby reference to a simple processing consisting of these steps insequence, viz., developing, fixing, washing and drying.

I prefer to pass each processing fluid through the unit in a continuousstream under pressure. To this end a supply of each may be maintainedunder pressure, as indicated schematically by the containers GI, 62, 63and 64 for the developer, fixing solution, wash and compressed air,respectively. The liquid containers may be elevated to give a staticpressure head, or they maybe subjected to air pressure above the liquidlevel, or their contents may be force-fed to the unit by a pump or bysuction. Lines from each container run to a header 65 or common lineleadingto the inlet line 42. In practice there may be such lines leadingfrom supply containers separate from the processing unit, or theprocessing unit and the containers with their control means may beincorporated in a single housing with internal fiow passages. It ispreferable to have as short a fiow as possible from the supply to theprocessing unit in order to minimize the quantity of each processingfluid remaining in the supply line after its step of processing iscompleted.

In each supply line is a valve 66, as indicated schematically, which maybe operated manually but is preferably operated automatically with atimer or indexing means to cause opening and closing of each valve atthe proper time in the cycle. The same cyclingmeans may be used tocontrol the film pull-down and the application of the forces to move themovable element It to and from working position in relation 'to thefilm.

First, when the film I is advanced to bring a frame to the processingstation, the movable element iii of the processingunit is brought intosealing engagement with the film by the pressure of air admitted throughline 3|. Then the valve in the line from the developer tank 6| is openedand that liquid fiows over the film face for the desired time. It iscontinuously discharged to waste through the outlet passage anddischarge line 43 which contains a lightly loaded check valve I0designed to maintain a back pressure of about 3 p. s. i., thus holdingthe fiuid under pressure at the processing station. At the end of thetime necessary for developing, the valve in that line is closed andsimultaneously the valve in the line from the fixer supply 62 is opened.The fixing solution then expels the remaining developer steam andcontinues to flow over the film for the neces-' sary time. By similarvalve operation, the wash water (63) follows, and thereafter air (64) isput through to dry the film. The final step is the retraction of themovable element 25 of the processing unit (by suction in line 31 afterreleasing the pressure in line 3|) and the pull-down of the film toremove the processed frame and advance the next frame to th processingstation. If desired, a drying step may be introduced after each step ofliquid processing, but this is not always necessary.

In my co-pending application filed herewith, Serial No. 35,493, entitledControl for Rapid Film Processing, I describe a particular system ofcontrol which takes advantage of the light path through the processingunit and the varying opacity of the film at different stages ofprocessing to effect a control of the supply valves through aphoto-electric cell and electronic relay.

We claim:

1. Apparatus for rapid processing of exposed photographic film,comprising a member presenting a flat supporting surface to the film atone side, a member movable into and out of engagement with the oppositeside of the film to hold it against said supporting surface duringprocessing, said movable member comprising a cupshaped part theperipheral rim of which engages the film and forms a fiuid sealtherewith around the area of film to be processed, spaced inlet andoutlet connections in the side wall of said cupshaped part, and a fillerpart within said cupshaped part and spaced from its inner surface in theregion of the inlet and outlet, said filler part having a transversesurface facing the said supporting surface at a level short of said rimto form with the film a shallow fiow passage across the area of film tobe processed, whereby processing fiuids may be passed in sequence frominlet to outlet in a confined thin stream across said film area.

2. Apparatus in accordance with claim 1 in which said supporting memberand said cupshaped part and filler have transparent parts forming alight path in register with a substantial part of the area of film to beprocessed.

3. Apparatus in accordance with claim 1 in which there is a valveassociated with said outlet adapted to maintain a predetermined backpressure on a fluid delivered under pressure through said fiow passage.

4. Apparatus in accordance with claim 1 in which there is also a fixedmember having a telescopic fit with said cup-shaped port, said fixedmember and movable cup-shaped member having cooperating piston andcylinder parts whereby said movable member may be actuatedpneumatically.

5. Apparatus for rapid processing of photographic film, comprising amember presenting a supporting surface to the film at one side, a secondmember having a fiuid chamber, a rim on said second member surroundingthe chamber and engageable with the opposite side of the film to form afluid seal therewith around the longitudinal passages leading along saidside wall from said inlet and outlet connections to, Y REFERENCES CITEDw I said transverse surface, whereby processing fluids The followingreferences are of record the may be passed in sequence from the inletconfile of this patent: nection along one of the longitudinal passages,and then across the transverse surface in a con- 5 UNITED STATES PATENTSfined thin stream and along the other longi- N mber Name Date tudinalpassage to the outlet connection. 2,048,128 Logan July 21, 1936 6.Apparatus according to claim 5, in which 2,221,055 Lundegardh Nov, 12,1940 the filler part is a removable block having 1ongi- 2,446,668 Tuttleet a1. Aug. 10, 1948 tudinal fins engaging said side wall and defining10 2,492,133 Cobb Dec. 27, 1949 said passages. I

CLIFTON M. TU'ITLE. PARIS H. STAFFORD.

